well, if you play with your right hand, you write with your right hand.. and punch with your right hand, you prefer the pint to be on your left hand while your at it! :P

this is the unscientific answer of the bunch lol

When I was first learning guitar, I began by fretting notes with my right hand, even though I am right handed. For a long time, I made little progress, until I switched and began to fret with my left hand. I quickly got a lot better and it seemed more...natural. If I had to guess I would say that it is something to do with the hemispheres of the brain, the right being the one that controls music, spacial awareness and creativity....which ofcourse controls the left hand

Television cameras frequently focus on the left-hand gymnastics of top performers. As a result, the importance of good bows, bowing and plucking are overlooked. The truth is, with a conventional "right-handed" instrument, the dominant right hand is where the real action occurs. Bowing or plucking ability allows players to both produce and control the sounds that they craft into their interpretation of music.

Left-hand fingering may look impressive, but once you learn the notes, that part of playing tends to become automatic. From there on the quality of each performance depends on the sound you produce with your right hand. In the case of the violin it depends on your ability to constantly vary the bowing speed, pressure, angle, distance from bridge, bounciness or smoothness and so on, to produce the end result you desire.

Plucking the guitar is just as complex, particularly for the right hand of a classical guitarist. This is where the music is "made".

Bows rarely make the headlines but they are much more sophisticated than just a stick. Good violinists realise the importance of a well-balanced and responsive bow, and top makes fetch thousands of dollars from performers and collectors.

Rod Kennedy, (A left-handed but conventional ex-professional violinist), Napier, New Zealand

Although I regard myself as left-handed, this only shows up in one-handed tasks. Thus I write left-handed, and play tennis left-handed, but I hold scissors, a golf club, or a cricket bat in the same way as a right-handed person. I'd find it very hard to use a knife and fork in the way that lefties are supposed to.

Interestingly I have always used a computer mouse in my right-hand, even though it's superficially a one-handed task; I suspect that's because it leaves my dominant hand free to use the keyboard.